Poly-N-acetyllactosamine is a unique carbohydrate composed of N-acetyllactosamine repeats. In particular, poly-N-acetyllactosamine chains are synthesized by repeated alternating additions of N-acetylglucosamine and galactose, catalyzed by -1,3-N-acetylglucosaminyltransferases (poly-N-acetyllactosamine synthase) and -1,4-galactosyltransferases. What is depicted and described in this MetaboCard is a single subunit structure. Poly-N-acetyllactosamine structures occur in mammalian glycoproteins in both N- and O-linked glycans. They represent a backbone for additional modifications by fucosyltransferases, sialyltransferases and sulfotransferases. These glycans have been suggested to be involved in biospecific interactions with selectins and other glycan-binding proteins. Moreover, the poly-Nacetyllactosamine chains in N-glycans have been found to promote tumor progression and metastasis (PMID: 12570780 ).

This compound belongs to the class of organic compounds known as fatty acyl glycosides of mono- and disaccharides. These are compounds composed of a mono- or disaccharide moiety linked to one hydroxyl group of a fatty alcohol or of a phosphorylated alcohol (phosphoprenols), a hydroxy fatty acid or to one carboxyl group of a fatty acid (ester linkage) or to an amino alcohol.

Catalyzes the transfer of sulfate to position 6 of non- reducing N-acetylglucosamine (GlcNAc) residues of keratan. Mediates sulfation of keratan in cornea. Keratan sulfate plays a central role in maintaining corneal transparency. Acts on the non- reducing terminal GlcNAc of short and long carbohydrate substrates that have poly-N-acetyllactosamine structures

Branching enzyme that converts linear into branched poly-N-acetyllactosaminoglycans. Introduces the blood group I antigen during embryonic development. It is closely associated with the development and maturation of erythroid cells. The expression of the blood group I antigen in erythrocytes is determined by isoform C.

Catalyzes the transfer of sulfate to position 6 of non- reducing N-acetylglucosamine (GlcNAc) residues and O-linked sugars of mucin-type acceptors. Acts on the non-reducing terminal GlcNAc of short carbohydrate substrates. However, it does not transfer sulfate to longer carbohydrate substrates that have poly-N- acetyllactosamine structures. Has no activity toward keratan. Not involved in generating HEV-expressed ligands for L-selectin. Its substrate specificity may be influenced by its subcellular location

Beta-1,3-galactosyltransferase that transfers galactose from UDP-galactose to substrates with a terminal beta-linked galactose residue. Has a preference for galactose-beta-1,4-xylose that is found in the linker region of glycosaminoglycans, such as heparan sulfate and chondroitin sulfate. Has no activity towards substrates with terminal glucosamine or galactosamine residues.

Beta-1,3-N-acetylglucosaminyltransferase that plays a role in the elongation of specific branch structures of multiantennary N-glycans. Has strong activity towards tetraantennary N-glycans and 2,6 triantennary glycans